
        var $=function(el){
            return (typeof el=='object')?el:document.getElementById(el);
        };
       var addCookie=function(objName,objValue,objHours){//添加cookie
            var str = objName + "=" + escape(objValue);
            if(objHours > 0){//为0时不设定过期时间，浏览器关闭时cookie自动消失
                var date = new Date();
                var ms = objHours*3600*1000;
                date.setTime(date.getTime() + ms);
                str += "; expires=" + date.toGMTString();
            }
            document.cookie = str;
            alert("添加cookie成功");
        };
        var getCookie=function(objName){//获取指定名称的cookie的值
            var arrStr = document.cookie.split("; ");
            for(var i = 0;i < arrStr.length;i ++){
                var temp = arrStr[i].split("=");
                if(temp[0] == objName){
                return unescape(temp[1]);
                }
            }
        };
        var delCookie=function(name){//为了删除指定名称的cookie，可以将其过期时间设定为一个过去的时间
            var date = new Date();
            date.setTime(date.getTime() - 10000);
            document.cookie = name + "=a; expires=" + date.toGMTString();
            alert("删除成功");
        };
        var add=function(){//添加Cookie
            var cookie_name = $("cookie_name").value;
            var cookie_value = $("cookie_value").value;
            var cookie_expireHours = $("cookie_expiresHours").value;
            if(cookie_name==""||cookie_value==""){
              alert("请填写完整Cookie的名称和值");
              return;
            }
            addCookie(cookie_name,cookie_value,cookie_expireHours);
        };
        var getall=function(){//读取所有保存的cookie字符串
            var str = document.cookie;
            if(str == ""){
             str = "没有保存任何cookie";
            }
           alert(str);
        };
        var get=function(){//读取单个该名称的cookie
            var cookie_name = $("cookie_name").value;
            var cookie_value = getCookie(cookie_name);
            if(cookie_name ==""){
               alert("请填写名称，根据名称进行查找");
             return;
            }
            if(cookie_value==null){
              cookie_value="没有该名称的cookie";
            }
            alert(cookie_value);
        };
        var del=function(){//删除该名称的cookie
            var cookie_name = $("cookie_name").value;
            if(cookie_name==""){
              alert("请填写名称，根据名称进行删除");
              return;
            }
            delCookie(cookie_name);
        };

